Interconnection of power grids in large regions, especially interconnection of “Sanhua” extra-high voltage synchronous large power grid, brings great challenges for safety, stability and reliable operation of power system. It is very important to increase test frequency of various dynamic monitoring and control systems, make the monitoring system functional, and build and improve intelligent monitoring, scheduling and control systems. At present, traditional equipment test method within power transmission and transformation station of power system and booster station of power plant is generally in situ test, i.e., connecting standard device to equipment under test in situ for voltage and current boosting, and then comparing and calculating the standard value and measured value to obtain test results; however, if such in situ test method cannot be expanded to synchronous simulation test between multiple transformer stations and booster stations of power plants, test of monitoring and control systems in large regions with multiple nodes cannot be carried out. Therefore, invention of a multi-node synchronous simulation test method for power system is of great significance for synchronous test of monitoring and control systems in large regions with multiple nodes and safe and steady operation of synchronous large power grids.